The analysis of the structure of cultivated or fruit-bearing hedgerows obtained by implementing the process and device of the invention can be used in order to optimize the results of different mechanical or manual inventions to be performed on these hedgerows, whether simultaneously during or subsequent to examining their structure.
The invention can be advantageously applied to the equipment of agricultural machines designed and used for the preliminary pruning of trained and/or staked vines, but it is emphasized and understood in reading the following description that the invention can be implemented to equip other types of agricultural machines such as machines for cultivating the soil, machines for treating plants, harvesting machines, etc. For this reason, reference to a preliminary pruning (or pre-pruning) machine, in the following description, would not be restrictive.
It is recalled that the purpose of the mechanical pre-pruning of the vine is to simplify later pruning work by eliminating the maximum amount of wood before manual pruning. During this preparatory mechanical operation, the wood or vine-shoots whose tendrils are fixed to the wires of the paling, are cut off and released. The main problems of this work consist in:                ensuring passage by the paling of the stakes which create an obstacle to the movement of the cutting instruments, the restriction being that the action of the machine must not be destructive with regard to the stakes and the wires of the paling or its own cutting instruments;        for vines trained with cordons, not damaging the cordons, and notably not cutting off any of the fruit.        
Most modern pre-pruning machines use rotary cutting systems. Machines with cutting bars are less widespread because disengaging them in order to pass by the stakes can not be done as quickly.
According to the most modern type of machines equipped with rotary cutting systems, the cutting off of the wood is ensured by at least one column of shredding wheels comprising an open circular guide whose periphery forms fingers. Inside the wheels, fixed blades (EP-0 312 126) or a circular saw (FR-2.576.481) ensure that the wood is cut off, acting in combination with the fingers. The cutting tools thus comprised are stacked on two vertical shafts placed on either side of the paling axis during the pre-pruning operation. The rotary instruments acting together for the cutting action are arranged in alternate rows and slightly crossing each other during work; the lower wheel of each paling can be comprised of a pruning shearing wheel for better finishing.
At the entrance to a row of vine stocks, as well as at the exit from this row, the wheel columns are moved out so as to not cut the abutment wires. These paling wires must be correctly installed so as to not become caught or cut off while the machine is operating on the row.
For the passage of stakes having an appropriate diameter, often made of wood or concrete, the wheels roll on the stakes and move away from them automatically, the pressure on the stakes being adjustable so that matching a sizeable density of vine-shoots does not cause an undesired opening of the cutting head; on the contrary, the force for the passage of the stakes must not be excessive so as to not risk damaging them.
However, when the stakes are comprised of steel profiles having a small cross-section, for example, 30 mm angle irons, the spacing between the pilings and the cutting head to allow for the passage of the stakes must be made manually since the stakes can seriously damage the cutting tools by penetrating into the fingers of the rotary guides. In such a situation, the wine growers prefer, in the majority of cases, to use pre-pruning machines with manually controlled opening which requires that the drivers of these machines be vigilant at all times. Very often, to not take any risks, the drivers prefer to open and close the cutting head at a distance from the stakes with a large safety margin, which has the disadvantage of leaving a sizeable quantity of the wood uncut.
When the vines are cordon-cultivated (cordon de Royat), for example, an advantageous application of the invention is to make it possible to keep the pre-pruning cutting instruments above and at a suitable distance from the cordon, in order to remove any risk of damage to the cordon and prevent the elimination of the fruit that is intended to be protected, while keeping the wood pruned as small as possible.
In fact, if it is possible to adjust the height of the cutting instruments of the machine, at the entrance to a row, their position relative to the cordon can be modified when they are moved on this row due to unevenness in the ground, in a manner so that in case of a sudden drop resulting from the passage of the machine into a cavity in the ground, the cordon can be damaged or robbed of its fruits.
Another interesting application of the invention is to perform a measurement of the speed of advancement of the machine, in a manner so as to make possible a permanent adaptation of the functioning conditions of the tools from the measurement of the speed of movement.
In fact, if you consider the pre-pruning machines of the type mentioned above, the peripheral speed of the wheels must be adapted to the speed of movement, an excessive speed of rotation of the wheels has the effect of pulling the wood to the back, whereas a very low speed of the wheels results in pushing the vegetation to the front. The adaptation of the speed of rotation of the wheels to the speed of movement of the machine can be obtained using a speed setting. In practice, the wine-grower chooses an operating speed and adjusts the setting as a result before entering the vine, so that if this speed changes along the way, the cutting instruments will not always work in the best conditions, which causes breakage of the wood, and sometimes, uprooting of the base of the vine.
Another advantage use of the analysis of the structure of the rows of the wines is to allow a setting for the health status of the wine plants.
Wine growing is developing towards a concept of “Precision Wine Growing” (Trademark) which involves noticing, using sensors, all of the significant characteristics of the plant making it possible to consider these characteristics on a GPS map, with regard to short and long-term optimization of the harvest.
The base characteristics of the vine which are essentially the quantity of grapes harvested, the sugar of the grapes, their acidity and the health status of the plant, are collected in a database that is conventionally called “wine base information” and then used to define the conditions in which the pruning, the fertilization, and the selection of the grapes for better vinification, etc.
Knowing the health status of each plant is a data that is of interest to every winegrower who wants to improve the quality of his product. In fact, the map of the vine is developed among other things as a function of the fertilization and the nature of the ground. This development is expressed by the growth, during the vegetative period, of vine-shoots which lose their leaves the following winter.
The health status of the vine is measured when it is pruned; the pruned vine-shoots are recovered, cut into small pieces and weighed. The weight of these vine-shoots will represent the characteristic of health status. It is obtained by comparing the vine-bases, one relative to the other, in comparing deficient health status to good health status. It is known that each health status must correspond to a certain quantity of grapes produced by the plant.
The pruning of the vine has the function of allowing on each vinestock a certain number of buds, which, in the context of their development, will make it possible to determine the volume of the harvest. It is known, for example, that the vine must have an average of 28,000 buds per hectare after the pruning operation. Currently, 28,000 buds/hectare is divided by the number of feet/hectare, which determines uniformly for each vine base, the number of fruit to be looked after per vine base.
Knowing that in a parcel of land, taking into account the heterogeneity of the ground and the conditions of exposure, the health status is not uniform, there is reason, in modern wine-growing, to divide up the 28,000 fruit/hectare not uniformly but as a function of the health status of the vine base.
The measurements made in the context of precision wine-growing must make it possible to measure the health status of each vine base in a manner so as to assign to it an appropriate number of fruit. It is thus necessary to evaluate this health status per vine base in an automated manner because it is unthinkable to perform the operation of weighing the wood for each vine base.
In the document EP-0.974.262, an automated pruning device for plants such as wine plants is described, comprising a chassis supporting a pruning device, a device for acquisition of images making it possible to record the position of the plant relative to the pruning device, and a treatment unit planned in order to send control signals for the adjustment of the position of the pruning device as a function of the images recorded from the trunk or main branch of the plant relative to the pruning device. The device for acquisition of images is comprised of a pair of television cameras placed in a manner so as to be able to point towards the skin, with one at an angle relative to the other.
The automated pruning device described in this document implements a system for image acquisition (television) which does not function without lighting (daylight or substitute lighting) and which functions poorly under strong lighting (the result, for example, of a strong sun) requiring the use of a screen. It does not function during the night without implementing lighting to substitute for the sun.
It does not appear that an automated pruning device according to the document EP-0.974.262 has been put on the market, so that to the knowledge of the applicant, in the domain of agricultural machines, there are not known to exist any processes and devices capable of making, both during the day and the night, analyses of the structure of fruit-bearing hedgerows such as vine rows, and of applying the resulting information of these analyses:                in order to obtain the automatic opening of the cutting head of the pre-pruning machines moving by stepping over the vine row, for passage of the stakes, when they are made of angle irons or have a reduced diameter that allows them to penetrate into the fingers of the shredding wheels; for constant adaptation to the speed of rotation of the wheels to the speed of movement of the machine;        with respect to the integrity of the cordon and the fruits to be protected, for cordon-trained vines;—for the measurement of the health status of the vine.        
On the other hand, the necessity to proceed with a manual opening of the cutting head for passage of the stakes does not make it possible to perform work at high speed with the current machines. In fact, either the opening of the cutting head is delayed as much as possible in order to cut off the greatest quantity of vineshoots possible, and, in this case, the cutting head comes to hit the stakes causing the stakes to progressively recede, or the opening of the cutting head is anticipated, and, in this case, a sizeable quantity of vegetation is left on the vinestocks next to the stakes.
The present invention proposes to correct the deficiencies mentioned above.